The present invention relates to a data processing structure having a plurality of processors and a data bus for data communication with a serial data structure.
Drive systems usually comprise a drive controller with control electronics, a transmission system and a motor. In particular in complex systems there may be a plurality of such drive systems in a small space, for example in the arm of a robot with a plurality of degrees of freedom in the direction of movement.
FIG. 1 shows a drive system which is known from the prior art for robots having a plurality of drive controllers 10A, 10B, . . . etc. Each of the drive controllers 10i (where i=A, B, . . . etc.) has a microcontroller (or microprocessor) 20i which in turn controls, for example, a motor or motor and transmission system (indicated in FIG. 1 by the arrow 25i). Each of the microcontrollers 20i is connected in each case in parallel with a field bus 30 via which each of the microcontrollers 20i can be controlled centrally by a central controller 50. For example a CAN (Control Area Network) bus system, such as is known in particular from the field of automobiles, is used for the field bus 30 here.
If the microcontrollers 20i are not already configured or if they are to be reconfigured individually or collectively, in each case there must be access from the outside to the respective microcontroller or microcontrollers 20i as configuration via the field bus 30 is not possible. The microcontroller 20i needs a minimum operating software in order to operate the field bus 30.
In order to avoid the microcontrollers 20i being accessed from the outside, and thus to reduce the expenditure on programming, each microcontroller 20i which is to be programmed can be accessed with a separate data bus 40i, typically a serial data bus with point to point structure such as an RS232 interface. As a result, in each case a feeder line of a data bus 40i is necessary from a central programming unit 60 for each microcontroller 20i to be programmed, as is illustrated in FIG. 1.
Although adding the data buses 40i for programming the microcontrollers 20i can significantly reduce the expenditure on programming and the microcontrollers 20i can be programmed individually and flexibly, the actual increased expenditure on cabling as a result of the individual feeder lines to the data buses 40i proves impractical in many cases, in particular if only a small amount of space is available, as in the case of a robot arm. As the number of necessary data buses 40i increases in each case, the existing space reserves are very quickly used up and a selection of microcontrollers 20i, which are each respectively equipped with a data bus 40i and are therefore freely programmable, has to be made in accordance with the space available.
It is an object of the present invention to provide a drive system having a plurality of drive controllers, in particular for applications in robots, in which the drive controllers are each freely programmable and which can be used even in applications where exacting requirements are made of the compactness of the system.